Oil cooler having viscosity controlled shutter valve



Jan. 2, 19.45.`

s. K. ANDERSEN OIL COOLER HAVING VISCOSITY CONTROLLE) SHUTTER VALVE Filed May 20, 1941 www lul

/////////////l7//////////Jf/// /l/l//l/ (Iftorneg Patented Jan. 2, 1945 l UNITED STATES PATENT 4orrici:

on. cooLER nAvNG vlsoosrrr ooN'rRoLLED snU'r'rER. VALVE Soren K. Andersen, Los Angeles, Calif., assigner to The Garrett Corporation, Airesearch Manufacturing Company division,

Los Angeles,

Calif., a corporation of California Application May 20, 1941, Serial No. 394,280 17 claims. (o1. 236-351) My invention relates to means for controlling scribed,'wherein a predetermined pressure drop is'normally causedin the ow of oil and this pressure drop is employed in the operation of parts of the device. Y

A furthei` object of the invention is to providea control of the general character set forth in the Oil coolers ordinarily include passages through ,Y

l which the oil to be cooled is conducted and adjacent passages comprising refrigerant means whereby heat is absorbed from the oil.y Simplicity and economy have dictated use of air as a refrigerant for passing through the refrigerant passages of the oil cooler, and accordingly `the present invention is disclosed in conjunction with an oil cooler having shutter means for controlling the flow of air through the air tubes or passages of the cooler.

It is an object of the invention to provide a control for a cooling device of the character described having means for producing a pressure differential between two zones in the path of flow of the oil, and to utilize this pressure differential in exercising control over the heat absorbing action of the cooler.

A further object ofthe invention is to` .provide a control for a cooling device wherein a pressure differential is produced between two zones in the path of flow of the oil and a by-pass vfor a ow of oil from one of these zones to the other is son of its construction is quickly responsive to changes-in the viscosity of the oil.

A vfurther object of the invention is to provide ,a control for an oil cooling device which controls I' the action of the oil cooler .with reference to the viscosity of oil wiich has been cooled by the oil preceding paragraphs having means for varying the pressure drop. In the preferred practice of the invention, the pressure .drop is under limited Jcontrol of a pressure responsiveelement connected to the -cooler in such a way that when pressure builds up in the cooler due to congealing of the oil, the shutter means associated with the cooler will be moved toward closed position, or the action of the regulating means of the cooler will be changed so that a Warm-up of the cooler will voccur to produce a thawing -out of I the congealed oil.

'Further objects andvadvanta'ges of the invention. will be brought out in the following part of the specification, which refers to a forni-of -my p invention which will overcome disadvantages and shortcomings appearing in devices previously -employed for this general purpose, as will be hereinafter pointed out. i I

Referring to the drawing which is forillustrative purposes only: f

Fig. 1 is a partly sectioned, schematic elevational view showing a preferred form .of my in- Fig. `2 is an enlarged ,sectional view taken'on a plane as indicated by the line 2-2 of Fig. 1.

In Fig. 1 I show an oil cooling device comprisingy an oil cooler I0 and shutter means Il for controllingv allow of air through-the cooler. The shutter means Il comprises shutters I2 arranged so as to bemoved by suitable levers I3 and linkage V I4 from the open position in vwhichthey are shown infull lines to the closed position thereof indicated by dotted linesJ 5.

The diagrammatically. shown cooler l0 comprises a shell I6 to which a fitting I1 is attached.

This tting l1 has an inlet opening I8 which may be connected, as by means@of-pipifig'l'lQvsritlithe'if oil pump of an associated internal combustion engine, not shown. The fitting I'l'has an outlet port 20 and a. bypass chamber 2|. Theoil to be cooler. In the' preferred practiceof the invenl tion, the control unit thereof is connected to the cool oil outlet of the cooler, but it willbe recognized that the control unit may be connected .otherwise to the cooler.

An object of the invention is to provide a control fora cooling device of the character decooled passes from. the inlet opening I8 into a 'Y As shown by arrows 23., this inlet oil mayfpass j through a cooler inletport 24' into the .oil spaces or passages within the shell I8`of the cooler I8,

, and the cooled oil may pass as indicated by the arrow 25 through the oil outlet opening 28 of the shell I8into the outlet port 28 of the tting. The

l the inletl opening I8, through the'muif 22 to the bypass chamber, as indicated by the'arrows a, during by-pass of oil as will be hereinafter described.

A control unit 21 is secured to the fitting I as shown in Fig. 1. This control unit 21, as clearly shown in Fig. 2, comprises a shell 28, forming an oil chamber 29 which is connected to the outlet 28 of the cooler through the outlet port 28, an oil outlet chamber 38, having an outlet opening 3I to which oil return piping 32 may be connected, and a chamber 33 whichv is connected to the bypasschamber 2I of the fitting I1.

To provide a contractile-expansile uid 'motor element for actuation of the shutter means Il, a cylinder 34 is provided having a plunger v3.5 therein, with a rightwardlyprojecting stem 38,' the outer end 31 of which is connected through a link 38 with the master operating leverI 39 of the shutter means Il. A compression spring 48 is provided to urge the plunger 35 leftward so that as fluid is drained from the cylinder` space 4I at the leftward end or the plunger 35, the plunger Willbe moved leftward andthe shutters I2 will be moved toward open position. l

A bore 42 extends outward from the oil chamber 29 of the control unit 21 and the outer portion of the bore 42 is expanded, as shown at 43, so asto provide a shoulder 44. The bore 42 is v 88 is normally prevented by a bypass vvalves 8l referred to as a blind bore 42, by reason of the fact that the outer end thereof is closed by reimovable closure means 45. .An intermediate portion of the Vbore 42 is connected with the chamber 33 through a passage 48 having a screen 41 at the inlet thereof. Between the mouth of the passage 48 and the .shoulder 44, there is an annular valve port 48 which connects with the cylinder space 4I through a passage 49. The bore 42 slidably receives a valve piston 58 having an annular recess 5I communicating with the passage 48.

The far end of the recess 5I is deflned by a cone shapedV wall 53, having a purpose which will be hereinafter described. The valve piston 58 is tubular and has a thin-walled tube 54 projecting therefrom into the oil chamber 29 and forming an elongated passage or orifice 55 through which oil may flow from the chamber 29 and thence through the yinterior of the piston 58 into the space 58 of the bore 42 beyond the far end of the piston 58, such now of oil being indicated by arrows 51. VThe space58 is connected with the outlet-,chamber 38 through a passage 8 8 havingl therein an orice insert 59 inwhidh a very short orifice opening 88 is formed.

The flow of oil from the cooler I8 is through azone'representedby the chamber 29 to a' zone represented-by the outlet chamber 30. PressureI drop means are provided ,betweenthe zones to produce a pressure diierential between the zones having acylindrical skirt 88 extending rightward therefrom 'and having a tubular stem 81 'which -receives and guides the stem 88 of the relief valve 8l. The rear or rightward end of the stem 81 of the valve has a iianged member 89 secured thereon, and a compression spring 18, disposed between the cylindrical insert 84 and the anged member 89, exerts a yieldable force tending to hold the valve 85 in closedv relation to the opening through the cylindrical insert 84, as shown in Fig. 2. The skirt 88 of the valve 85 has openings 1I therein spaced from the leftward or front end ofthe valve, so that before oil can pass from the chamber 33 into the outlet chamber 34, the valve 85 must move a prescribed distance against the restraining force of the spring 10 and so as to compress'the spring 83, and tol 'engage and compress an auxiliary spring 12, aswill be later described. I

The present device exercises its controlof the cooler I8 with reference to the outlet oil temperature, thereby avoiding the many difliculties resulting from the attempt to employ the temperature of the oil as it leaves the engine as a referl ence fora control, for the yreason that it has been found that the temperature of the'oil leaving the engine, or passing into the inlet of the cooler will, as a general rule, remain fairly constant for quite a wide variation in the temperature of the oil returned from the cooler to the engine. The present invention also avoids the many ditllculties en.; countered in an attempt to employ the pressure drop across the cooler as a reference for control of the cooler, since it has been found that the flow from various engines varies as much as and the devices of this type, although tailor-made to suit the presumed conditions of operation in each l'individual engine, fail to. accomplish the desired purpose by reason ofthe undependableness of this pressure drop across the cooler, responsibility for which is partly due to fluctuations in the pressure of the oil delivered from the engine to the cooler.

Oil, leaving the cooler as indicated by arrow 25 in Fig. l, passes into the chamber 29, and leaves this chamber through two separate paths.` One path of exit for the'cooled oil is through the port differential produced by the valve 6I and its assoand to normally produce a predetermined pressure in the chamber 29. This pressure drop means' comprises a relief valve l8l urged left- -wardly so as to close the port 82 between the chambers 29- and 38 by yieldable means comprising a spring 83. The chamber 33 is connected v with the outlet chamber 38 through the opening provided by a cylindrical inserta, and now of oil from the chamber 33 'to the outlet chamber ciated parts. The spring 83 is of such size that it will normally produce a pressure differential of about ve pounds per square inch between the chambers 29'and 38. This pressure diierential is exerted against the piston 58, tending to move the same against a compression spring 13 adjustably disposed in the space 58. The movement of this pressure responsive means is under control of the' viscosity of the oil which passes through thebypass. The inlet orice into the space 58, namely, the elongated passage 55, due toits length and relative slenderness, produces a variation in the -inlet iiow of oil from the chamber 29 to the' spacel 58 in proportion to the variations in the viscosity of the oil.v The outlet orifice 88 of the space 58, being relatively short, controls the outlet now of oil from the space 58 with reference Lto changes in pressure in the oil, but with very little `changein flow due to changes in viscosity. Accordingly, as the viscosity of the oil increases, there will bea reduction in the rate I of ow of oil into the space 56; 'with' a consequent increase in pressure diierential between the front and rear ends of the piston 50, sov that thepiston will be moved in adirection to connect,the passage 46 and the annular space 5| with theport 48 or, if the valve is already open, in a direction to increase the flow of oil from the space through the port 48 and the passage 49 into .the

cylinder space 4|. In a converse manner, heating up of the oil and consequent reduction in the viscosity thereofv will result in an increased rate of flow of oil into the' chamber or spacev 56 so as to increase the pressure therein and produce shutter control for. oil cooler, now Patent No'.-

2,288,8'17, dated' July 7, 1942. My present construction, however, is an improvement-l over the disclosure of my copending application. The viscosity responsive orice 55 is formed by a thinwalled tube 54 which projects into Athe chamber 23. This gives a greater sensitivity of operation for the reason that theA response to changes in viscosity are not retarded as a result of the necessity for the oil stream passing through the passage 55 to change theA temperature of the Wall forming this passage. 'I'he wall 5 4 is relatively thin, and the temperature thereof is quickly changed by external contact to conform 'to the temperature ofthe oil in the chamber 29.

Also, the present arrangement avoids the use of a screen in front of the resistance-passage 55, and the diameter of this .passage 55 is sucient to readily pass such particles as might be carried by the oil. -It has been observed that when a screen is placed in front of the resistance tube and this screen becomes clogged, the result will be to close th shutter means Il. On the other hand, if the creen is'left off, as shown, and the orifice 60 should become clogged, the shutters will be held open, ay condition which is not as serious as the other.

,The high pressure oil used for moving the plunger 35 is received through the passage 46 from the chamber 33 which is connected through the mui 22 with the inlet opening 4|8.` This high pressure oil passes into the 4space 5| around a portion of the piston 5'0, and the oil pressure on the piston isbalanced from all sides, so that it may be said that the piston floats in oil. Likewise, as the piston 50 is forced back against the action ofl the spring 13, oil will pass all around the cone shaped wall 53 into the annular port 48- and the oil,wi1l rlow out evenly on al1 sides of the piston, with the resulty that the piston 50 is centered by the oilfjlow. In the arrangement shown, theccne shaped wall 53 provides -for a metering of the oil as it passes from the space 8| to the port 48, and it is found thatin the arrangement shown, the force requiredv to shear off the oil flow at the point of closing is negligible and that maximum freedom of movementot` the piston 50 under control of the differential of. y forces axially applied, is maintained. I The position of the plunger 35 inthe cylinder 34 is determined by the pressure and volumeof` the oil accumulating adjacentthe leftward v-face of thel plunger 35 as a result of thev balancing of the iniiow of fluid through the passage 4 8 with the outow through the bleeder passage 14, which connectsI the cylinder space 4| with the outlet chamber 30.

Variations in pressure in the interior of Athe cooler In are reflected in the pressure variations n the 'warm-up passage or interior of the mui 22. Accordingly, the pressure in the bypass vlchamber 2| of the fitting Il and in the thereto connected chamber 33 will vary in accordance ,with the pressure in the coolen Congealing of oil within the cooler will increase the pressure required to force the oilthrough the cooler, and

when this pressure reaches a value determined by the strength of the spring 10, Fig. *2, the bypass valve will be forced leftward and oil will be bypassed through the openings 1I, from the interior Aof the mutt 22 into the outlet chamber 30. This leftward movement of the bypass valvev 65 will' result in the application of increased leftward pressure, throughithe springs 63 and 12, against the pressure drop or pressure differential valve 6I so that there' Will be` an increase in the pressure ydifferential between the chamber 29-and the chamber 30, due to the fact 4thatv the escape of oil from the chamber 29 is restricted. This increase in pressure in the chamber 29 will cause the pilot valve 50 to open, thereby producing an increased ow of oil into the cylinder space 4I so that the eplunger 15 will be moved rightwardly and a closing action of the shutter means will be attained, therebyvreducingor shutting off the flow of air through the cooler, so'that a warming up of the irterior of the cooler will occur to thaw out the congealed oil. After this thaw-out operation, the normal I vtemperature-viscosity control of the shutter means will be resumedas a result of the return of the respective parts of the device to their normal positions of operation I claim as my invention:

1. In an oil cooling device of the character described, the combination of: a cooler adapted to receive oil to be cooled; pressure drop means to produce a pressuredrop in oil which has been cooled in said cooler; bypass means for bypassing a flow of said oil from one side to the other of/ said pressure drop means; means for varying the cooling action of said cooler; means sensi- 2. In an oil cooling device of the character den scribed, the combination of: a cooler adapted to receive oil to be cooled; pressure drop means to lproduce a pressure drop in oil which has been cooled in said cooler; bypass means for bypassing a flow of said oil from one side to the other of said pressure'drop means; means for varying the cooling action `of said cooler; means sensitive to changes in the viscosity and pressure of the oil passed through said 'by-pass means for controlling the operation of said means for varying the cooling capacity, of the cooler; and means responsive to pressure conditions in said cooler resulting from the thickening of oil therein to change the action of said pressure drop means so as to increase said pressure drop.

3. In an oil cooling deviceof the character vdescribed, the combination of: a cooler adapted 4, c accusa to receive oil to be cooled; pressure drop'means -to produce a. pressure drop in oil which has been cooled in, said cooler; bypass means for bypassing a ow of said oil from one side to the other of said pressure drop means; means for varying the cooling action of said cooler: control means operated by the flow and `pressure of oil through said bypass for controlling the action of said means for varying the capacity of said cooler; andmeans responsive to pressure conditions 'outlet means for said chamber; obypass'means connecting the interior of said chamber with said system following said'pressure drop outlet means; shutter control means acting in response tothe pressure-and condition of the oil ilow through said bypass means to actuate said shut-l ter means; and means operating in response to increase. in pressure in said cooler inlet resulting fromy the thickening of oil in said cooler to actuate said vpressure drop means so that it will increase the pressure in said chamber.

8. In a control means foruse with an oil cooling device comprising a coolerhaviing an inlet,

. an outlet. and associated shutter' means, the

bination of: a shell forming a chamber having an inlet to receive oil which issues from the oil circulating 'system associated with the cooler;

pressure drop outlet means for said chamber, for t holding a pressure in said'chamber; means rel sponsiveto pressure in said chamber to actuate said shutter means; and means operating in response to increase in pressurein said cooler inlet resulting from the thickening of oil in said- 4 cooler to actuate said pressure drop'means so that it will increase the pressure in said cham- 5. In a control means for use with an oil cooling device comprisinga cooler having an inlet,'

'an outlet, and associated shutter means, the

combination of: a shell forming a. chamber hav.v

.ing an inlet to receive' oil which' passes through the oil circulating system which is connectedto said cooler; pressure drop outlet means for said j chamber; lbypass means connecting the interior of said chamber with said system following said pressure drop outlet means; shutter -control v meansacting'in rssponseto4 the pressure and conditionl of the-*oil ow through said bypass means to actuatesaid shutter means; and means' operating in response' 'to increase in pressure in said cooler inlet resulting fromy the thickening of oil in said c'oolerto actuate said'pressure drop means so that it will increasethe pressure in said j chamber.V 1

6. In acontrol means for use with an oil cooling devioecomprising a cooler having an inlet, an outlet, and associated lshutter means. the combination of: a shell forming aV chamber having an circulating system which is connected vto said cooler; nrSSure drop outlet means for said cham* ber; bypass means connecting the interior of said v chamber with said system following'said pressure combination of a shell ,forming a chamber having an inlet for connection toan oil circulating system so asto receive oil which has been cooled by said oil cooler; pressure `drop outlet means for said chamber; bypass means connecting the vinterior of said chamber with said system following said pressure dropoutlet means; shutter control means acting in response to the pressure and condition of the oil flow through said bypass means to actuate said shutter means, said shutter controlmeans comprising a part rendering it sensitive t'o i changes inviscosity in the oil comprising said bypass ow of oil; and means operatingin response toincrease in pressurein said cooler inlet resulting from'the thickening of oil in said cooler to actuate said'pressure drop means so that itv will-increase the pressure in said chamber.'

9. 1n a control unit for an 011 cooling device Vof the character described, the combination of: a shell forming a chamber inlet and an outlet means for holding a pressure in said chamber but permitting an outletgiiow through said outlet means; a motor; means responsive to pressure in said chamber to control the operation of said motor; and means-.additional to said outlet means operative to vary the action of said outlet means so .as to increase the pressurevin said chamberv in response to thickening of oil' in the cooler and thereby vary the operation of.-

- said motor. e

10. Ina control unit for an oil cooling device l lof the character described, the combination of:

, a shell forming a chamber having an inlet and an outlet means for holding a pressure in said Y inlet to receive oil which passes through the oil drop outlet means; shutterV control means acting in response to the 4pressure and condition ofthe oil now through said bypass meansto actuate 'I said shutter means, saidshutter control means comprising a rendering it sensitive to1d changes in viscosity in th'e Yoil 'comprising said '1 bypassflow of oil; and means 'operating-in respouse to increase in pressure in said cooler in. let resulting from the thickening of oil in said cooler-to actuate said pressure drop means 'so lat it will increase 4the pressure in said chamr. y 7. In a. vcontrol means for use with an voil .cooling device comprising a cooler having an inlet, an outlet, and associated shuttenineans, the combination of: a sheilA forming a chamber having an inlet for connection to an oil circulating system so as to receive 'oil which' has been cooled by said oil fcooler; pressure drop chamber but permitting an outlet ow through said outlet means; a.,motor; means responsive to pressure in said chamber to control the operation 'of said motor; means having aipart exposed to the -oil, in 'said inlet so that it will be nioved in response Ato changes 'in fluid pressure applied toit; `and means operated by. the movement of said part so as to vary the action of said outlet ,means A so as .to increase the ypressure in said chamber and thereby'vary the operation of said motor. 'i f 11. In a' system for controlling the action of an oil cooling 'device of thecharacter described,

the combination of: means for producing a pressure differential between two zones in the path of iiow of the oil; means operative in response to changes in said'pressurediiferential to vary the action of said oil cooling device; and means additional to said pressure di'erential means for causing 'said pressurediierential to be increased in response to-thickening of oil in the cooler,

l2, In a system for controlling the action of an oil' cooling'device of the character described,

the combination of: meanstfor producing a pres- 'sure diierential between two zonesin the path I oi-flow of the oil; means operative' in response to changes in said pressure diierential to vary ential actingto move .said

space; valve means-operating in accordance with ,l

tnegaction or said ou cooling device; and means operative in response to changes .in pressurevin va part of saidv oil cooling device resulting from the thickening of oil therein for said pressure differential 'to be increased.

v 13. In a system for .controlling theacti0n of an oil cooling device of the character described;

` the. combination of: means for producing a pressure diierential between two zones in the path of iiow ofthe oil: means forming a bypass connecting said zones;A means vresponsive to changes in pressure dierential .and changes'in viscosity in the oil flow through said bypass to vary the action of said oil cooling device; and means operative-in response to changes in pressure in a part of said oil coolingdevice resulting cfronithe thickening of -oil'therein for causing said pressure differential to be increased. l

14. In a control unit for an oi1 cooling device of the character described, the combination of:

a shell forming a chamber having an inlet open,- ing to receive oil and an outletopening, with pressure-drop means disposed between said vchamber and said outlet opening; an expansile contractile motor element; a blind bore leading outward vfrom said chamber; a piston in said bore,

said piston having an elongated orifice l.extending therethrough; yieldable means to urge said Y piston toward said chamber; means formingY a. short orice leading out from the space of'said which varies in pressure in accordance 'with the movement of said piston to control a iiow or oiltosaid motor element to actuate the same; means for connecting said motor element to the control Amechanism of the oil cooling device; wallsforming a pressure chamber to receive oil the changes in the pressure .in said oil coolu ing device as the result of the thickening of vIl() said cooler, the combination of; a shell forming a chamber having an inlet to receive oil from the oil circulating system which is connected to said cooler; pressure drop outlet means for said cham ber;

said chamber with -said oil circulating system following said pressure drop outlet means; 'control means acting in response to the pressure and 'bore behind said piston, whereby the pressure. Y

dinerential actingito move said piston will inf 'crease as theresult ofl thickening-*of the oil which 'flows through said space;` valve means operating in accordance with th/'e movement of ,said piston tol controla now of oil to said motor element to actuate the same; and means for connecting said motor element to the control mechanism o'f the oil cooling device.

15. In' a control unitior an oil 'cooling device of the character described, the combination oi: a

shell formi g a chamber having ansinlet opening to receive il and an outlet opening. with pressure drop means disposed between said chamber andsaidoutlet opening; an expansile con tractile motor element; ablind bore'leading outconc'lition, of the oil now through said bypass Vmeans to control said regulating means; s and means operating inv response to increase in pres-l sure in said lcooler inlet resulting from the thickening of oil in said coolerl to actuate said pressure drop means so that it will increase the pressure in said chamber. f 1'1. In a control means for and an4 oil outlet and cooler` regulating means 40 for controlling "the heat absorbing characteristics of lsaid cooler, the combination of: a shell forniing a chamber havingan inlet to receive oil from cooler; pressure drop outlet means for said cham- 45 ber, for-holding a pressureiin said' chamber;

, means responsive to'pressure'in said chamber to ward-fromsaid chamber; a piston in said bore, 1-

said piston having an elongated orifice extending therethrough; yieldablelmeans to urgeisaid pis- -ton toward said chamber; means forming a short orifice leading out from the space of said bore behind said piston, wherebythe pressure difierviscosity o!A the oil which lso piston will vary with e il'ows through said control said regulating means; and means oper-- in pressure in said ating' in .response to increase the thickening of cooler inlet 'resulting lfrom oil in said cooler to 'actuate said pressure drop.-

means so that it will increase the pressure in said chamber;

soREN K.

bypass means connecting the interior of v use with an oil cool#l ing device comprising a cooler lhaving an oil inlet y the oil circulating-system associated with said ACERTIFICA'LE 0F coRRETIN-f Patent' No; 2,566,586;

' sREN- K.. ANDERSEN,

It 1e hereby certifiedA that errer appears' vi'rrthe fri'ittepcffietioh of the above numbered patent requiring eet'onas fol'icmgef age 5, e't tplm, line rha '-claim 12, after the word "fprf ihsert -.mipg1.; and that the said Letters Patent' shmi'ldberead Awith .this corretioh' =thtnrfein that the same may tgnfbm ttf.` the patera 'ofA the ease vvLnf'the Pateht effige.

signed yhpa-tened'this;'-10th. 1ay f Apr-11H, A. 19g-117915;

.Leslie Frazer 

